The present invention relates to certain novel naphthopyran compounds. More particularly, this invention relates to novel photochromic naphthopyran compounds and to compositions and articles containing such novel naphthopyran compounds. When exposed to light radiation containing ultraviolet rays, such as the ultraviolet radiation in sunlight or the light of a mercury lamp, many photochromic compounds exhibit a reversible change in color. When the ultraviolet radiation is discontinued, such a photochromic compound will return to its original color or colorless state.
Various classes of photochromic compounds have been synthesized and suggested for use in applications in which a sunlight-induced reversible color change or darkening is desired. U.S. Pat. No. 3,567,605 (Becker) describes a series of pyran derivatives, including certain benzopyrans and naphthopyrans. These compounds are described as derivatives of chromene and are reported to undergo a color change, e.g., from colorless to yellow-orange, on irradiation by ultraviolet light at temperatures below about xe2x88x9230xc2x0 C. Irradiation of the compounds with visible light or upon raising the temperature to above about 0xc2x0 C. is reported to reverse the coloration to a colorless state.
U.S. Pat. No. 5,066,818 describes various 3,3-diaryl-3H-naphtho[2,1-b]pyrans as having desirable photochromic properties, i.e., high colorability and acceptable fade, for ophthalmic and other applications. Also disclosed by way of comparative example in the ""818 patent are the isomeric 2,2-diaryl-2H-naphtho[1,2-b]pyrans, which are reported to require unacceptably long periods of time to fade after activation.
U.S. Pat. No. 3,627,690 describes photochromic 2,2-di-substituted-2H-naphtho[1,2-b]pyran compositions containing minor amounts of either a base or weak-to-moderate strength acid. The addition of either an acid or base to the naphthopyran composition is reported to increase the fade rate of the colored naphthopyrans, thereby making them useful in eye protection applications such as sunglasses. It is reported therein further that the fade rate of 2H-naphtho[1,2-b]pyrans without the aforementioned additives ranges from several hours to many days to reach complete reversion. U.S. Pat. No. 5,458,814 discloses 2H-naphtho[1,2-b]pyrans substituted in the 5- and 6-positions that possess a reasonable rate of fade as well as high colorability. The compounds exhibit activated colors ranging from yellow to red/purple.
While the activated form of a typical organic photochromic molecule absorbs in the visible region over a relatively narrow range (Van Gemert and Kish, PPG Technology Journal, Vol. 5, pg. 53-61, 1999), naphthopyrans having two absorption bands, are known. U.S. Pat. No. 5,645,767 discloses photochromic indeno[2,1-f]naphtho[1,2-b]pyrans having a blue/gray activated color. A blue/gray color will be perceived when there is a major absorption of visible light in the 580-620 nm range coupled with a minor absorption in the 420-500 nm range.
International Patent Application Publication No. WO 99/15518 discloses photochromic indeno[2,1-f]naphtho[1,2-b]pyrans having a green activated color. A greenish color will be perceived when there is a major absorption of visible light in the 580-620 nm range coupled with a major absorption of roughly equal intensity in the 400-480 nm range.
International Patent Application Publication No. WO 98/42693 describes naphtho[1,2-b]pyrans having amino functional groups as substituents at the 7- or 9-positions of the naphthopyran ring. These compounds are disclosed as exhibiting a brown or red/brown activated color. A red/brown color will be perceived when there is a major absorption of visible light in the 420-500 nm range coupled with a minor absorption in the 520-560 nm range.
International Patent Application Publication No. WO 98/04937 describes naphtho[1,2-b]pyrans having alkoxy groups as substituents at the 7- and 9-positions of the naphthopyran ring. The activated forms of these compounds exhibit two intense absorption bands in the visible light range. It is reported that the optical density of the band absorbing at lower wavelengths (band xe2x80x9cAxe2x80x9d) in some cases is higher than the optical density of the band absorbing at higher wavelengths (band xe2x80x9cBxe2x80x9d), but in the majority of cases the band xe2x80x9cAxe2x80x9d is of lower optical density than band xe2x80x9cBxe2x80x9d.
International Patent Application Publication No. WO 00/35902 describes 2H-naphtho[1,2-b]pyrans having various substituents. It is disclosed that when a substituent is present at the 5 carbon atom of a 2,2-diaryl-2H-naphtho[1,2-b]pyran, the intensity of the color generated can be enhanced by placing an electron-releasing group at the 8 carbon atom. This effect may be further augmented by placing additional electron-releasing groups at carbon atoms 7 and/or 10. It is further disclosed that the intensity of the generated color can be diminished by placing electron-releasing substituents at carbon atoms 9 or 7. There is no mention in this application of the naphthopyrans having multiple absorption bands nor the relative intensities of such bands.
While it is obvious from the previous description that it is possible to obtain many complex activated colors, it is not disclosed in any of these patents or applications how to select substituents for both the pyrano and the naphtho portions of the naphtho[1,2-b]pyran in order to control the wavelength and/or intensity of the absorbance bands within the activated visible spectra.
The present invention discloses what types of substituents and where they may be placed in order to control the wavelength and/or intensity of the visible absorbance bands of 2H-naphtho[1,2-b]pyrans having 2 intense spectral bands in the visible spectrum. Such 2H-naphtho[l,2-b]pyrans are essentially characterized by either two adjacent moderate to strong electron donor substituents at the 8 and 9 positions or a fused heterocyclic group formed by the substituents at the 8 and 9 positions coming together and at the 2 position, weak to moderate electron donor substituent(s). The compounds of the present invention also have a substituent at the 5 position and an optional substituent at the 6 position. The selection and placement of these substituents being done so that the photochromic naphthopyrans demonstrate a rating of at least 80 in the Relative xcex94OD at Saturation Test, described hereinafter.
Clearly with this understanding, not only can compounds exhibiting colors including an apparent blended brown, gray or a green activated color be obtained, but one skilled in the art can now fine tune the activated visible spectrum to meet specific needs. For example, the use of certain individual compounds of the present invention may eliminate the need for combining two or more compounds to obtain a preferred shade or version of the neutral colors such as gray or brown. In addition, these compounds have demonstrated a high molar absorptivity (or molar extinction coefficient) in the ultraviolet (UV) light range, an acceptable fade rate without the addition of acids or bases, a high activated intensity, and a high coloration rate. These compounds are also reported to be more resistant to fatigue than other compounds having equal absorbance in the 400 to 500 nanometer range.
In recent years, photochromic plastic materials, particularly plastic materials for optical applications, have been the subject of considerable attention. In particular, photochromic ophthalmic plastic lenses have been investigated because of the weight advantage they offer, vis-a-vis, glass lenses. Moreover, photochromic transparencies for vehicles, such as cars and airplanes, have been of interest because of the potential safety features that such transparencies offer.
In accordance with the present invention, it has now been discovered that certain novel 2H-naphtho[1,2-b]pyrans having an xe2x80x9cAxe2x80x9d band in the 420-500 nm region and a xe2x80x9cBxe2x80x9d band in the 480-620 nm region of the activated visible spectrum and having a rating of 80 or higher in the Relative xcex94OD at Saturation Test may be prepared. The Relative xcex94OD at Saturation Test is described in Example 9. The ratings of the test are defined herein as the result obtained when the optical density of band xe2x80x9cAxe2x80x9d is divided by the optical density of band xe2x80x9cBxe2x80x9d and multiplied by 100. It is believed that compounds having a rating of 80 or higher are most valuable for formulating neutral grays, greens and browns for commercial photochromic ophthalmic eyeware.
The naphthopyrans of the present invention may have a rating in the Relative xcex94OD at Saturation Test of at least 80, preferably at least 90, more preferably at least 100 and most preferably, at least 130. The rating is expected to be less than 1000, preferably less than 800, more preferably less than 500 and most preferably less than 300. The rating for the naphthopyrans may range between any combination of these values, inclusive of the recited values, e.g., from at least 80 to less than 1000. The naphthopyrans of the present invention may have a rating greater than 1000 if the two absorption bands are distinguishable and an optical density is obtainable for the calculation.
Preparation of such compounds is achieved by balancing the effects of the potential substituents as described hereinafter. For example, the xe2x80x9cAxe2x80x9d band of these compounds can be enhanced relative to the xe2x80x9cBxe2x80x9d band by employing strong electron donor substituents in the 8-position, moderate electron donors in the 9-position, and weak to moderate electron donors in the 2-position of the pyran ring. Compounds having relatively equivalent intensity for the xe2x80x9cAxe2x80x9d and xe2x80x9cBxe2x80x9d bands can be obtained by having electron donors of relatively equal intensity at the 8- and 9-positions and weak to moderate electron donors at the 2-position of the pyran ring. Strong electron donors on an aryl grouping at the 2-position of the pyran will enhance the xe2x80x9cBxe2x80x9d band relative to the xe2x80x9cAxe2x80x9d band. The intensity or strength of the electron donors at the 2-position of the pyran ring will not only effect the relative intensity of the two spectral bands, but also their position. For example, strong electron donors on an aryl grouping at the 2-position will shift both bands bathochromically (the xe2x80x9cBxe2x80x9d band more than the xe2x80x9cAxe2x80x9d band).
The relative strength of electron donor groups is frequently described by Hammett Sigma values (specifically "sgr"p values). A tabular listing of "sgr"p constants for a variety of substituents can be found in xe2x80x9cExploring QSAR, Hydrophobic, Electronic, and Steric Constants, C. Hansch, A. Leo, and D. Hoekman, Eds., Published by The American Chemical Society, Washington, D.C., 1995, which disclosure is incorporated herein by reference. Examples of strong electron donors, defined herein as having a Hammett "sgr"p value of between xe2x88x921.0 and xe2x88x920.5, that may be used at the 8- and 9-positions or at the para position of an aryl grouping present at the 2-position of the pyrano portion of the naphthopyran include amino, monoalkylamino, dialkylamino, morpholino, and piperidino. Examples of moderate electron donors, defined herein as having a "sgr"p value of between xe2x88x920.49 and xe2x88x920.20 that may be used at the 8- and 9-positions or at the para position of an aryl grouping present at the 2-position of the pyrano portion of the naphthopyran include ethoxy, methoxy, and p-aminophenyl. Examples of weak electron donors, defined herein as having a Hammett "sgr"p value of between xe2x88x920.01 and xe2x88x920.19 that may be used at the 2-position of the pyrano portion of the naphthopyran include methyl, ethyl, phenyl, naphthyl, and tolyl.
The compounds of the present invention may be described as photochromic compounds of 2H-naphtho[1,2-b]pyran structure, essentially characterized by having moderate to strong electron donor groups R3 and R4 at the 8 and 9 positions, respectively, or a heterocyclic ring fused to the j side of the naphtho portion of the compound and at the 2 position, weak to moderate electron donor substituents. Also present are substituents at the 5 position and optionally, at the 6 position of the naphtho portion of the compound. These compounds may be represented by the following graphic formula I in which the letters a through n on the outside of the ring structure represent the sides of the naphthopyran ring, and the numbers on the inside of the ring structure represent the numbers of the ring carbon atoms or ring positions of the naphthopyran: 
In graphic formula I, the substituent R4 is the following group (i) and R3 is selected from the group consisting of (i), (ii), (iii) and (iv):
(i) the group, xe2x80x94OR12, wherein R12 is hydrogen, C1-C6 alkyl, the unsubstituted, mono- and disubstituted aryl groups, phenyl and naphthyl, phenyl(C1-C3)alkyl, mono(C1-C6)alkyl substituted phenyl(C1-C3)alkyl, mono(C1-C6)alkoxy substituted phenyl(C1-C3)alkyl, C1-C6 alkoxy(C2-C4)alkyl, C3-C7 cycloalkyl, mono(C1-C4)alkyl substituted C3-C7 cycloalkyl, C1-C6 chloroalkyl, C1-C6 fluoroalkyl, allyl or R12 is the group xe2x80x94CH(R13)Q, wherein R13 is hydrogen or C1-C3 alkyl and Q is xe2x80x94CN, xe2x80x94CF3 or xe2x80x94COOR7 (R7 being the same as defined hereinafter), each of said phenyl and naphthyl group substituents being C1-C6 alkyl or C1-C6 alkoxy;
(ii) the group, xe2x80x94N(R14)R15, wherein R14 and R15 are each selected from the group consisting of hydrogen, C1-C8 alkyl, phenyl, naphthyl, the heteroaromatic groups furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, dibenzofuranyl, dibenzothienyl, benzopyridyl and fluorenyl, a C1-C8 alkylaryl group, C3-C20 cycloalkyl, C4-C20 bicycloalkyl, C5-C20 tricycloalkyl and C1-C20 alkoxyalkyl, wherein said aryl group is phenyl or naphthyl;
(iii) a nitrogen containing ring represented by the following graphic formula: 
xe2x80x83wherein W is selected from the group consisting of xe2x80x94CH2xe2x80x94, xe2x80x94CH(R16)xe2x80x94, xe2x80x94C(R16)(R16)xe2x80x94, xe2x80x94CH(aryl)xe2x80x94, xe2x80x94C(aryl)2xe2x80x94, xe2x80x94C(R16)(aryl)xe2x80x94, and G is selected from the group consisting of xe2x80x94Wxe2x80x94, xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94S(O)xe2x80x94, xe2x80x94S(O2)xe2x80x94, xe2x80x94NHxe2x80x94, xe2x80x94NR16xe2x80x94 and xe2x80x94N-aryl, wherein R16 is C1-C6 alkyl, aryl is phenyl or naphthyl, m is the integer 1, 2 or 3, and p is the integer 0, 1, 2 or 3 and when p is O, G is W; and
(iv) a group represented by the following graphic formulae: 
xe2x80x83wherein R18, R19 and R20 are each hydrogen, C1-C5 alkyl, phenyl or naphthyl, or the groups R18 and R19 may come together to form a saturated or unsaturated ring of 5 to 8 carbon atoms including the ring carbon atoms. For example, when R18 and R19 come together to form a ring of 6 carbon atoms on the group represented by graphic formula IIB, the resulting unsaturated group is carbazol-9-yl and the saturated group is tetrahydrocarbazol-9-yl. R17 is C1-C6 alkyl, C1-C6 alkoxy, fluoro or chloro.
Alternatively, R3 and R4 together form the following graphic formula: 
wherein J and K are each oxygen or the group xe2x80x94NR14xe2x80x94; R14, R18 and R19 being the same as defined hereinbefore.
Preferably, R4 is the following group (i); and R3 is selected from the group consisting of:
(i) the group xe2x80x94OR12, wherein R12 is hydrogen, C1-C4 alkyl, an unsubstituted, mono- or di-substituted phenyl, phenyl(C1-C2)alkyl, mono(C1-C4)alkyl substituted phenyl(C1-C2)alkyl, mono(C1-C4)alkoxy substituted phenyl(C1-C2)alkyl, C1-C4 alkoxy(C2-C3)alkyl, C3-C5 cycloalkyl, mono(C1-C4)alkyl substituted C3-C5 cycloalkyl, C1-C4 chloroalkyl, C1-C4 fluoroalkyl, allyl, each of said phenyl substituents being C1-C3 alkyl or C1-C3 alkoxy;
(ii) the group, xe2x80x94N(R14)R15, wherein R14 and R15 are each selected from the group consisting of hydrogen, C1-C4 alkyl, phenyl, C1-C6 alkylphenyl, C3-C10 cycloalkyl, and C1-C10 alkoxyalkyl; and
(iii) a nitrogen containing ring represented by graphic formula IIA wherein W is selected from the group consisting of xe2x80x94CH2xe2x80x94, xe2x80x94CH(R16)xe2x80x94, xe2x80x94C(R16)(R16)xe2x80x94, xe2x80x94CH(aryl)xe2x80x94, xe2x80x94C(aryl)2xe2x80x94, xe2x80x94C(R16)(aryl)xe2x80x94, and G is selected from the group consisting of xe2x80x94Wxe2x80x94, xe2x80x94Oxe2x80x94, xe2x80x94NHxe2x80x94, xe2x80x94NR16xe2x80x94 and xe2x80x94N-aryl, wherein R16 is C1-C4 alkyl and aryl is phenyl or naphthyl, m is the integer 1, 2 or 3, and p is the integer 0, 1, 2 or 3 and when p is O, G is W.
Alternatively, R3 and R4 together form graphic formula IIE wherein J and K are each oxygen or the group xe2x80x94NR14xe2x80x94; R14, R18 and R19 being the same as defined herein before.
More preferably, R4 is the following group (i); and R3 is selected from the group consisting of:
(i) the group, xe2x80x94OR12, wherein R12 is hydrogen or C1-C3 alkyl;
(ii) the group, xe2x80x94N(R14)R15, wherein R14 and R15 are each hydrogen or C1-C3 alkyl; and
(iii) a nitrogen containing ring represented by graphic formula IIA wherein W is xe2x80x94CH2xe2x80x94 and G is selected from the group consisting of xe2x80x94Wxe2x80x94 and xe2x80x94Oxe2x80x94, m is the integer 1 or 2, p is the integer 0, 1 or 2, and when p is O, G is W.
Alternatively, R3 and R4 together form the compound represented by graphic formula IIE wherein J and K are each oxygen.
In graphic formulae I, R1 may be the group T; R2 may be the group T or a mono-T-substituted phenyl. The T group may be represented by the general formula:
xe2x80x94E[(OC2H4)x(OC3H6)y(OC4H8)z]Exe2x80x2 or
xe2x80x94[(OC2H4)x(OC3H6)y(OC4H8)z]Exe2x80x2
wherein xe2x80x94E is xe2x80x94C(O)xe2x80x94 or xe2x80x94CH2xe2x80x94, and Exe2x80x2 is C1-C3 alkoxy or a polymerizable group, i.e., any functional group capable of participating in a polymerization reaction. Polymer forming methods in which the compounds of the present invention may participate include radical polymerization, and such other polymerization processes as are described in Ullmann""s Encyclopedia of Industrial Chemistry, xe2x80x9cPolymerization Processesxe2x80x9d, Vol. 21A, pp 305 to 428, which disclosure is incorporated herein by reference. The polymerizable groups may be selected from the group consisting of hydroxy, (meth)acryloxy, and epoxy, e.g., oxiranylmethyl. When there are 2 or more polymerizable groups on the naphthopyran, they may be the same or different
The group, xe2x80x94(OC2H4)xxe2x80x94, represents poly(ethylene oxide); xe2x80x94(OC3H6)yxe2x80x94, represents poly(propylene oxide); and, xe2x80x94(OC4H8)zxe2x80x94, represents poly(butylene oxide). When used in combination, the poly(ethylene oxide), poly(propylene oxide) and poly(butylene oxide) groups of T may be in a random or block order within the T moiety. The letters x, y and z are each a number between 0 and 50 and the sum of x, y and z is between 2 and 50. The sum of x, y and z may be any number that falls within the range of 2 to 50, e.g., 2, 3 . . . 50. The sum may also range from any lower number to any higher number within the range of 2 to 50, e.g., 6 to 50, 31 to 50. The numbers for x, y, and z are average values and can be partial numbers, e.g., 9.5.
Alternatively, the substituents R1 or R2 in graphic formula I may be a group other than T or mono-T-substituted phenyl. R1 may be selected from xe2x80x94CH2X, xe2x80x94C(V)2X or xe2x80x94C(O)Y, wherein: X is hydrogen, C1-C6 alkyl, chloro, fluoro, bromo, hydroxy, benzoyloxy, C1-C6 alkoxy, C2-C6 acyloxy, amino, mono(C1-C6)alkylamino, di(C1-C6) alkylamino, morpholino, piperidino, 1-indolinyl, pyrrolidyl, trimethylsilyloxy or the group, xe2x80x94OCH(R7)Z; V is C1-C6 alkyl or the unsubstituted, mono- or di-substituted aryl groups, phenyl or naphthyl, said aryl group substituents being C1-C6 alkyl or C1-C6 alkoxy; Y is hydrogen, hydroxy, C1-C6 alkyl, the unsubstituted, mono- or di-substituted aryl groups phenyl or naphthyl, the group, xe2x80x94OCH(R7)Z, xe2x80x94OR8, or xe2x80x94N(R9)(R10) or an unsubstituted, mono-substituted or di-substituted heterocyclic ring selected from the group consisting of 1-indolinyl, morpholino, piperidino, 1-pyrrolidyl, 1-imidazolidyl, 2-imidazolin-1-yl, pyrazolidyl, pyrazolinyl and 1-piperazinyl, each of said phenyl, naphthyl and heterocyclic ring substituents being C1-C6 alkyl or C1-C6 alkoxy; Z is xe2x80x94CN, xe2x80x94CF3, chloro, fluoro, or xe2x80x94C(O)R11; R7 is hydrogen or C1-C6 alkyl; R11 is hydrogen, C1-C6 alkyl or C1-C6 alkoxy; R8 is hydrogen, C1-C6 alkyl, allyl, phenyl(C1-C3)alkyl, mono(C1-C6)alkyl substituted phenyl(C1-C3)alkyl, mono(C1-C6)alkoxy substituted phenyl(C1-C3)alkyl, (C1-C6)alkoxy(C2-C4)alkyl, C1-C6 haloalkyl, or the unsubstituted, mono- or di-substituted aryl groups, phenyl or naphthyl, each of said phenyl and naphthyl group substituents being C1-C6 alkyl or C1-C6 alkoxy, said halo substituents being chloro or fluoro; and R9 and R10 are each selected from the group consisting of hydrogen, C1-C6 alkyl, C5-C7 cycloalkyl, phenyl, mono-substituted phenyl and di-substituted phenyl, said phenyl substituents being C1-C6 alkyl or C1-C6 alkoxy.
Preferably, R1 is selected from xe2x80x94CH2X, xe2x80x94C(V)2X or xe2x80x94C(O)Y, wherein: X is hydrogen, C1-C4 alkyl, hydroxy, benzoyloxy, C1-C4 alkoxy, C2-C4 acyloxy, amino, mono(C1-C4)alkylamino, di(C1-C4)alkylamino, morpholino, piperidino, 1-indolinyl, pyrrolidyl; V is C1-C4 alkyl or the unsubstituted, mono- or di-substituted aryl groups, phenyl or naphthyl, said aryl group substituents being C1-C4 alkyl or C1-4 alkoxy; Y is hydrogen, hydroxy, C1-C4 alkyl, an unsubstituted, mono- or di-substituted phenyl, the group, xe2x80x94OCH(R7)Z, xe2x80x94OR8, or xe2x80x94N(R9)(R10) or an unsubstituted or mono-substituted heterocyclic ring selected from the group consisting of 1-indolinyl, morpholino, piperidino, and 1-pyrrolidyl, each of said phenyl and heterocyclic ring substituents being C1-C4 alkyl or C1-C4 alkoxy; Z is xe2x80x94CN or xe2x80x94C(O)R11; R7 is hydrogen or C1-C4 alkyl; R11 is C1-C4 alkyl or C1-C4 alkoxy; R8 is hydrogen, C1-C4 alkyl, phenyl(C1-C2)alkyl, mono(C1-C4)alkyl substituted phenyl(C1-C2)alkyl, mono(C1-C4)alkoxy substituted phenyl(C1-C2)alkyl, mono(C1-C4)alkoxy(C2-C3)alkyl, or an unsubstituted, mono- or di-substituted phenyl, each of said phenyl substituents being C1-C4 alkyl or C1-C4 alkoxy, and R9 and R10 are each selected from the group consisting of hydrogen, C1-C4 alkyl, C5-C6 cycloalkyl, phenyl, mono-substituted phenyl and di-substituted phenyl, said phenyl substituents being C1-C4 alkyl or C1-C4 alkoxy.
More preferably, R1 is selected from xe2x80x94CH2X, xe2x80x94C(V)2X or xe2x80x94C(O)Y, wherein: X is hydrogen, C1-C3 alkyl, hydroxy, benzoyloxy, C1-C3 alkoxy, C2-C3 acyloxy, amino, mono(C1-C3)alkylamino, di(C1-C3)alkylamino, morpholino or piperidino; V is C1-C3 alkyl or an unsubstituted or mono-substituted phenyl, said phenyl group substituents being C1-C3 alkyl or C1-C3 alkoxy; Y is hydrogen, hydroxy, C1-C3 alkyl, an unsubstituted or mono-substituted phenyl, the group, xe2x80x94OR8, or xe2x80x94N(R9)(R10) or an unsubstituted or mono-substituted heterocyclic ring selected from the group consisting of 1-indolinyl, morpholino and piperidino, each of said phenyl and heterocyclic ring substituents being C1-C3 alkyl or C1-C3 alkoxy; R8 is hydrogen or C1-C3 alkyl; and R9 and R10 are each selected from the group consisting of hydrogen, C1-C3 alkyl, phenyl and mono-substituted phenyl, said phenyl substituent being C1-C3 alkyl or C1-C3 alkoxy.
R2 in graphic formula I may be selected from hydrogen, C1-C6 alkyl, C1-C6 alkoxy, the unsubstituted, mono- or di-substituted aryl groups, phenyl or naphthyl, amino, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, phenylamino, mono- or di-(C1-C6)alkyl substituted phenylamino, mono- or di-(C1-C6)alkoxy substituted phenylamino, diphenylamino, mono- or di-(C1-C6)alkyl substituted diphenylamino, mono- or di-(C1-C6)alkoxy substituted diphenylamino, morpholino, piperidino, dicyclohexylamino or pyrrolidyl, said aryl substituents being selected from the group consisting of C1-C6 alkyl, C1-C6 alkoxy, C3-C6 cycloalkyl, benzyl, amino, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, dicyclohexylamino, diphenylamino, piperidino, morpholino, pyrrolidyl, pyridyl, bromo, chloro, fluoro, phenyl and naphthyl.
Preferably, R2 is selected from hydrogen, C1-C4 alkyl, C1-C4 alkoxy, the unsubstituted, mono- or di-substituted aryl groups, phenyl or naphthyl, amino, mono(C1-C4)alkylamino, di(C1-C4)alkylamino, morpholino, piperidino, or pyrrolidyl, said aryl substituents being selected from the group consisting of C1-C4 alkyl, C1-C4 alkoxy, C3-C5 cycloalkyl, benzyl, amino, mono(C1-C4)alkylamino, di(C1-C4)alkylamino, piperidino, morpholino, chloro, fluoro and phenyl. More preferably, R2 is hydrogen, C1-C3 alkoxy, C1-C3 alkyl or unsubstituted, mono- or di-substituted phenyl, said phenyl substituents being C1-C3 alkyl, C1-C3 alkoxy, chloro or fluoro.
B and Bxe2x80x2 in graphic formula I may each be selected from the group consisting of:
(i) mono-T-substituted phenyl;
(ii) the unsubstituted, mono-, di-, and tri-substituted aryl groups, phenyl and naphthyl;
(iii) 9-julolidinyl and the unsubstituted, mono- and di-substituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, dibenzofuranyl, dibenzothienyl, carbazoyl, benzopyridyl, indolinyl and fluorenyl, each of said aryl and aromatic heterocyclic substituents in parts (ii) and (iii) being selected from the group consisting of hydroxy, aryl, mono(C1-C6)alkoxyaryl, di(C1-C6)alkoxyaryl, mono(C1-C6)alkylaryl, di(C1-C6)alkylaryl, chloroaryl, fluoroaryl, C3-C7 cycloalkylaryl, C3-C7 cycloalkyl, C3-C7 cycloalkyloxy, C3-C7 cycloalkyloxy(C1-C6)alkyl, C3-C7 cycloalkyloxy(C1-C6)alkoxy, aryl(C1-C6)alkyl, aryl(C1-C6)alkoxy, aryloxy, aryloxy(C1-C6)alkyl, aryloxy(C1-C6)alkoxy, mono- and di-(C1-C6)alkylaryl(C1-C6)alkyl, mono- and di-(C1-C6)alkoxyaryl(C1-C6)alkyl, mono- and di-(C1-C6)alkylaryl(C1-C6)alkoxy, mono- and di-(C1-C6)alkoxyaryl(C1-C6)alkoxy, amino, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, diarylamino, piperazino, N-(C1-C6)alkylpiperazino, N-arylpiperazino, aziridino, indolino, piperidino, morpholino, thiomorpholino, tetrahydroquinolino, tetrahydroisoquinolino, pyrrolidyl, C1-C6 alkyl, C1-C6 chloroalkyl, C1-C6 fluoroalkyl, C1-C6 alkoxy, mono(C1-C6)alkoxy(C1-C4)alkyl, acryloxy, methacryloxy, bromo, chloro and fluoro, each aryl group described for said aryl or heteroaromatic substituent being phenyl or naphthyl;
(iv) the unsubstituted or mono-substituted groups, pyrazolyl, imidazolyl, pyridyl, pyrazolinyl, imidazolinyl, pyrrolinyl, phenothiazinyl, phenoxazinyl, phenazinyl or acridinyl, each of said substituents for said groups in (iv) being selected from the group consisting of C1-C6 alkyl, C1-C4 alkoxy, phenyl, fluoro, chloro and bromo;
(v) monosubstituted phenyl, having a substituent at the para position that is a linking group, xe2x80x94(CH2)txe2x80x94 or xe2x80x94Oxe2x80x94(CH2)txe2x80x94, wherein t is the integer 1, 2, 3, 4, 5 or 6, connected to an aryl group, e.g. phenyl or naphthyl, which is a member of another photochromic naphthopyran, such as naphtho[2,1-b]pyran or naphtho[1,2-b]pyran;
(vi) the groups represented by the following graphic formulae: 
xe2x80x83wherein A is methylene or oxygen and D is oxygen or substituted nitrogen, provided that when D is substituted nitrogen, A is methylene, said nitrogen substituents being selected from the group consisting of hydrogen, C1-C6 alkyl, and C2-C6 acyl; each R23 is C1-C6 alkyl, C1-C6 alkoxy, hydroxy, chloro or fluoro; R21 and R22 are each hydrogen or C1-C6 alkyl; and q is the integer 0, 1, or 2;
(vii) C1-C6 alkyl, C1-C6 chloroalkyl, C1-C6 fluoroalkyl, C1-C6 alkoxy(C1-C4)alkyl, C3-C6 cycloalkyl, mono(C1-C6)alkoxy(C3-C6)cycloalkyl, mono(C1-C6)alkyl(C3-C6)cycloalkyl, chloro(C3-C6)cycloalkyl, fluoro(C3-C6)cycloalkyl and C4-C12 bicycloalkyl; and
(viii) the group represented by the following graphic formula: 
xe2x80x83wherein L in graphic formula IIH may be hydrogen or C1-C4 alkyl and M in graphic formula IIH may be selected from the unsubstituted, mono-, and di-substituted members of the group consisting of naphthyl, phenyl, furanyl, and thienyl, each of said group substituents in this part (vii) being C1-C4 alkyl, C1-C4 alkoxy, fluoro, or chloro.
Alternatively, B and Bxe2x80x2 taken together may form fluoren-9-ylidene, mono-, or di-substituted fluoren-9-ylidene or form a member selected from the group consisting of saturated C3-C12 spiro-monocyclic hydrocarbon rings, e.g., cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononylidene, cyclodecylidene cycloundecylidene, and cyclododecylidene, saturated C7-C12 spiro-bicyclic hydrocarbon rings, e.g., bicyclo[2.2.1]heptylidene, i.e., norbornylidene, 1,7,7-trimethyl bicyclo[2.2.1]heptylidene, i.e., bornylidene, bicyclo[3.2.1]octylidene, bicyclo[3.3.1]nonan-9-ylidene, bicyclo[4.3.2]undecane, and saturated C7-C12 spiro-tricyclic hydrocarbon rings, e.g., tricyclo[2.2.1.02,6]heptylidene, tricyclo[3.3.1.13,7 ]decylidene, i.e., adamantylidene, and tricyclo[5.3.1.12,6 ]dodecylidene, each of said fluoren-9-ylidene substituents being selected from the group consisting of C1-C4 alkyl, C1-C4 alkoxy, fluoro and chloro.
Preferably, B and Bxe2x80x2 are each selected from the group consisting of: (i) phenyl, mono-substituted phenyl, and di-substituted phenyl, preferably substituted in the meta and/or para positions; (ii) the unsubstituted, mono- and di-substituted aromatic heterocyclic groups furanyl, benzofuran-2-yl, thienyl, benzothien-2-yl and dibenzofuranyl, each of said phenyl and aromatic heterocyclic substituents in parts (i) and (ii) being selected from the group consisting of hydroxy, amino, mono(C1-C3)alkylamino, di(C1-C3)alkylamino, piperidino, morpholino, pyrryl, C1-C3 alkyl, C1-C3 chloroalkyl, C1-C3 fluoroalkyl, C1-C3 alkoxy, mono(C1-C3)alkoxy(C1-C3)alkyl, fluoro and chloro; (iii) the groups represented by the graphic formulae IIF and IIG, wherein A is methylene and D is oxygen, R23 is C1-C3 alkyl or C1-C3 alkoxy, R21 and R22 are each hydrogen or C1-C3 alkyl; and q is the integer 0 or 1; (iv) C1-C4 alkyl; and (v) the group represented by the graphic formula IIH wherein L is hydrogen or methyl and M is phenyl or mono-substituted phenyl, said phenyl substituent being selected from the group consisting of C1-C3 alkyl, C1-C3 alkoxy, and fluoro; or (vi) B and Bxe2x80x2 taken together form fluoren-9-ylidene, mono-substituted fluoren-9-ylidene or a member selected from the group consisting of saturated C3-C8 spiro-monocyclic hydrocarbon rings, saturated C7-C10 spiro-bicyclic hydrocarbon rings, and saturated C7-C10 spiro-tricyclic hydrocarbon rings, said fluoren-9-ylidene substituent being selected from the group consisting of C1-C3 alkyl, C1-C3 alkoxy, fluoro and chloro.
More preferably, B and Bxe2x80x2 are each selected from the group consisting of (i) phenyl, mono- and di-substituted phenyl, (ii) the unsubstituted, mono- and di-substituted aromatic heterocyclic groups furanyl, benzofuran-2-yl, thienyl, benzothien-2-yl and dibenzofuranyl, each of said phenyl and aromatic heterocyclic substituents being selected from the group consisting of hydroxy, C1-C3 alkyl, C1-C3 alkoxy, fluoro and chloro; and (iii) the group represented by graphic formula IIF, wherein A is methylene and D is oxygen, R23 is C1-C3 alkyl or C1-C3 alkoxy, R21 and R22 are each hydrogen or C1-C3 alkyl, and q is the integer 0 or 1; or (iv) B and Bxe2x80x2 taken together form fluoren-9-ylidene, adamantylidene, bornylidene, norbornylidene, or bicyclo[3.3.1]nonan-9-ylidene.
Compounds represented by graphic formula I, which have the substituents R1-R4, B and Bxe2x80x2 described hereinbefore, may be prepared by the following Reactions A through F. Methods for preparing compounds represented by graphic formula I wherein R3 is an amino group are included in Reaction E. Preparation of Compound I wherein R3 and R4 together form a heterocyclic ring is described in Reaction F.
Methods for the preparation of compounds wherein R1, R2, B and/or Bxe2x80x2 is the polyalkoxylated group T are described in U. S. Pat. No. 5,961,842, which disclosure is incorporated herein by reference. Methods for the preparation of compounds wherein R1, R2, B and/or Bxe2x80x2 is the polymerizable polyalkoxylated group T are described in U. S. application Ser. No. 09/151,911, filed Sep. 11, 1998, which application is incorporated herein by reference.
Compounds represented by graphic formula V, VA, or VB are either purchased or prepared by Friedel-Crafts methods shown in Reaction A using an appropriately substituted or unsubstituted benzoyl chloride of graphic formula IV with a substituted or unsubstituted benzene compound of graphic formula III, which may be commercially available. See the publication Friedel-Crafts and Related Reactions, George A. Olah, Interscience Publishers, 1964, Vol. 3, Chapter XXXI (Aromatic Ketone Synthesis), and xe2x80x9cRegioselective Friedel-Crafts Acylation of 1,2,3,4-Tetrahydroquinoline and Related Nitrogen Heterocycles: Effect on NH Protective Groups and Ring Sizexe2x80x9d by Ishihara, Yugi et al, J. Chem. Soc., Perkin Trans. 1, pages 3401 to 3406, 1992.
In Reaction A, the compounds represented by graphic formulae III and IV are dissolved in a solvent, such as carbon disulfide or methylene chloride, and reacted in the presence of a Lewis acid, such as aluminum chloride or tin tetrachloride, to form the corresponding substituted benzophenone represented by graphic formula V (VA in Reaction B or VB in Reaction C). R and Rxe2x80x2 represent possible substituents, as described hereinbefore with respect to graphic formula I. 
In Reaction B, the substituted or unsubstituted ketone represented by graphic formula VA, in which B and Bxe2x80x2 may represent groups other than substituted or unsubstituted phenyl, as shown in graphic formula V, is reacted with sodium acetylide in a suitable solvent, such as anhydrous tetrahydrofuran (THF), to form the corresponding propargyl alcohol represented by graphic formula VI. Propargyl alcohols having B or Bxe2x80x2 groups other than substituted and unsubstituted phenyl may be prepared from commercially available ketones or ketones prepared via reaction of an acyl halide with a substituted or unsubstituted benzene, naphthalene or heteroaromatic compound, e.g., 9-julolidinyl. Propargyl alcohols having a B or Bxe2x80x2 group represented by graphic formula IIH may be prepared by the methods described in U.S. Pat. No. 5,274,132, column 2, lines 40 to 68. 
In Reaction C, a substituted benzophenone or benzaldehyde represented by graphic formula VB is reacted with an ester of succinic acid such as dimethyl succinate represented by graphic formula VII. Addition of the reactants to a solvent, e.g., toluene, containing potassium t-butoxide or sodium hydride as the base yields the Stobbe condensation half ester represented by graphic formula VIII. A mixture of cis and trans half esters forms which then undergoes cyclodehydration in the presence of acetic anhydride to form a mixture of acetoxynaphthalenes. Further purification to isolate the distinct isomer IX may be required. This product is hydrolyzed in methanol with hydrochloric acid to form the carbomethoxynaphthol represented by graphic formula X. 
In Reaction D, the carbomethoxynaphthol represented by graphic formula X is coupled with a propargyl alcohol represented by graphic formula VI in the presence of a catalytic amount of an acid, e.g., dodecylbenzene sulfonic acid (DBSA), in a solvent, e.g., chloroform, to produce the naphthopyran represented by graphic formula IA. 
Reaction E along with the procedures described in Reactions C and D are followed to produce amino substituted naphthopyrans. In Reaction E, the ketone represented by graphic formula VC is reacted with a lithium salt of an amine represented by graphic formula XI in a solvent such as tetrahydrofuran (THF) to produce the amino substituted ketone represented by graphic formula XII. Treatment of compound XII with dimethyl succinate to produce the corresponding ester, followed by cyclization with acetic anhydride and subsequent methanolysis as described in Reaction C produces the corresponding amino substituted naphthol. The amino substituted naphthol is then coupled with propargyl alcohol as described in Reaction D to produce amino substituted naphthopyrans. 
Reaction F along with the procedures described in Reactions C and D are followed to produce naphthopyrans having a heterocyclic ring fused thereto. In Reaction F, the compounds represented by graphic formulae XIII and XIV are dissolved in a solvent, such as carbon disulfide or methylene chloride, and reacted in the presence of a Lewis acid, such as aluminum chloride or tin tetrachloride, to form the corresponding substituted benzaldehyde, benzophenone, or acetophenone represented by graphic formula XV. Treatment of compound XV with dimethyl succinate to produce the corresponding ester, followed by cyclization with acetic anhydride and subsequent methanolysis as described in Reaction C produces the corresponding heterocyclic fused naphthol. The heterocyclic naphthol is then coupled with propargyl alcohol as described in Reaction D to produce heterocyclic fused naphthopyrans. 
Compounds represented by graphic formula I may be used in those applications in which organic photochromic substances may be employed, such as optical lenses, e.g., vision correcting ophthalmic lenses, contact lenses and plano lenses, face shields, goggles, visors, camera lenses, windows, automotive windshields, aircraft and automotive transparencies, e.g., T-roofs, sidelights and backlights, plastic films and sheets, textiles and coatings, e.g., coating compositions such as paints, and verification marks on security documents, e.g., documents such as banknotes, passports and drivers"" licenses for which authentication or verification of authenticity may be desired. Naphthopyrans represented by graphic formula I exhibit blended color changes from colorless to colors of orange/brown to green. These blended color changes are a result of one absorption band (band xe2x80x9cAxe2x80x9d) in the 420-500nm region and another absorption band (band xe2x80x9cBxe2x80x9d) in the 480-620nm region
Other than in the operating examples, or where otherwise indicated, all numbers expressing wavelengths, quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the term xe2x80x9caboutxe2x80x9d.
Examples of contemplated naphthopyran compounds within the scope of the invention are the following:
(a) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-(3,4-dimethoxyphenyl)-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(b) 2,2-diphenyl-5-methoxycarbonyl-6-(3,4-dimethoxyphenyl)-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(c) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-phenyl-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(d) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-phenyl-9,10-dihydro-2H-[1,4]dioxino[2xe2x80x2,3xe2x80x2:8,9]naphtho[1,2-b]pyran;
(e) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-phenyl-8-morpholino-9-methoxy-2H-naphtho[1,2-b]pyran;
(f) 2-(4-methoxyphenyl)-2-phenyl-5-methoxycarbonyl-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(g) 2,2-diphenyl-5-methoxycarbonyl-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(h) 2,2-di-(4-methoxyphenyl)-5-methoxycarbonyl-8,9-dimethoxy-2H-naphtho[1,2-b]pyran;
(i) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-phenyl-8-piperidino-9-methoxy-2H-naphtho[1,2-b]pyran;
(j) 2,2-di(4-methoxyphenyl)-5-methoxycarbonyl-6-methyl-8,9-dimethoxy-2H-naphtho[1,2-b]pyran; and
(k) 2,2-diphenyl-5-methoxycarbonyl-6-phenyl-2H-[1,3]dioxolo[4xe2x80x2, 5xe2x80x2:8,9]naphtho[1,2-b]pyran.
It is contemplated that the organic photochromic naphthopyrans of the present invention may be used alone, in combination with other naphthopyrans of the present invention, or in combination with one or more other appropriate complementary organic photochromic materials, i.e., organic photochromic compounds having at least one activated absorption maxima within the range of between about 400 and 700 nanometers, or substances containing same, and may be incorporated, e.g., dissolved or dispersed, in a polymeric organic host material used to prepare photochromic articles and which color when activated to an appropriate hue.
Examples of complementary organic photochromic compounds include other naphthopyrans and indenonaphthopyrans, chromenes and oxazines, substituted 2H-phenanthro[4,3-b]pyran and 3H-phenanthro[1,2-b]pyran compounds, benzopyran compounds having substituents at the 2-position of the pyran ring and mixtures of such photochromic compounds. Such photochromic compounds are described in U.S. Pat. Nos. 3,562,172; 3,567,605; 3,578,602; 4,215,010; 4,342,668; 4,816,584; 4,818,096; 4,826,977; 4,880,667; 4,931,219; 5,066,818; 5,238,981; 5,274,132; 5,384,077; 5,405,958; 5,429,774; 5,458,814, 5,466,398; 5,514,817; 5,552,090; 5,552,091; 5,565,147; 5,573,712; having a thickness ranging from 1 to 50 microns may be applied by conventional methods used in coating technology. Coatings of a thickness greater than 50 microns may require molding methods typically used for overlays. A preferred coating composition is polyurethane prepared from organic polyol(s).
The complementary organic photochromic materials may also include polymerizable photochromic compounds, such as those disclosed in U.S. Pat. Nos. 4,719,296; 5,166,345; 5,236,958; 5,252,742; 5,359,035; and 5,488,119.
Other complementary photochromic substances contemplated are metal-dithiozonates, e.g., mercury dithizonates which are described in, for example, U.S. Pat. No. 3,361,706; and fulgides and fulgimides, e.g., the 3-furyl and 3-thienyl fulgides and fulgimides, which are described in U.S. Pat. No. 4,931,220 at column 20, line 5 through column 21, line 38.
The disclosures relating to such photochromic compounds in the aforedescribed patents are incorporated herein, in toto, by reference. The photochromic articles of the present invention may contain one photochromic compound or a mixture of photochromic compounds, as desired.
The photochromic compounds of the present invention may be associated with a polymeric organic host material or other substrate by various means. They may be incorporated, i.e., dissolved and/or dispersed, into the host material, polymerized with other components of the host material, and/or incorporated into a coating applied to a substrate, e.g., a polymeric coating applied to one surface of the polymeric organic host material.
Each of the photochromic substances described herein may be used in amounts (or in a ratio) such that an organic host material or substrate to which the photochromic compounds or mixture of compounds is associated, exhibits a desired resultant color, e.g., a substantially neutral color when activated with unfiltered sunlight, i.e., as near a neutral color as possible given the colors of the activated photochromic compounds. Neutral gray and neutral brown colors are preferred. Further discussion of neutral colors and ways to describe colors may be found in U.S. Pat. No. 5,645,767 column 12, line 66 to column 13, line 19.
The amount of the photochromic naphthopyrans to be applied to or incorporated into a coating composition or host material is not critical provided that a sufficient amount is used to produce a photochromic effect discernible to the naked eye upon activation. Generally such amount can be described as a photochromic amount. The particular amount used depends often upon the intensity of color desired upon irradiation thereof and upon the method used to incorporate or apply the photochromic compounds. Typically, the more photochromic compound applied or incorporated, the greater is the color intensity up to a certain limit.
The relative amounts of the aforesaid photochromic compounds used will vary and depend in part upon the relative intensities of the color of the activated species of such compounds, the ultimate color desired and the method of application to the host material or substrate. Generally, the amount of total photochromic compound incorporated into or applied to a photochromic optical host material may range from about 0.05 to about 2.0, e.g., from 0.2 to about 1.0, milligrams per square centimeter of surface to which the photochromic compound is incorporated or applied. The amount of photochromic material incorporated into a coating composition may range from 0.1 to 40 weight percent based on the weight of the liquid coating composition.
The photochromic naphthopyrans of the present invention may be associated with the host material by various methods described in the art. See, for example, column 13, lines 40 to 58 of U.S. Pat. No. 5,645,767. Aqueous or organic solutions of the photochromic compounds may be used to incorporate the photochromic compounds into a polymeric organic host material or other materials such as textiles and polymeric coating compositions. Polymeric coating compositions may be applied to the substrate using a coating process such as that described in U.S. Pat. No. 3,971,872, the disclosure of which is incorporated herein by reference.
Application of the polymeric coating may be by any of the methods used in coating technology such as, for example, spray coating, spin coating, spread coating, curtain coating, dip coating, casting or roll-coating and methods used in preparing overlays, such as the method of the type described in U.S. Pat. No. 4,873,029, which is incorporated herein by reference. The application method selected also depends on the thickness of the cured coating. Coatings having a thickness ranging from 1 to 50 microns may be applied by conventional methods used in coating technology. Coatings of a thickness greater than 50 microns may require molding methods typically used for overlays. A preferred coating composition is polyurethane prepared from organic polyol(s) and an isocyanate. The photochromic substances of the present invention may be dissolved or dispersed within the organic polyol component or isocyanate component of the polyurethane coating or may be added to a mixture of the polyurethane-forming components.
The host material will usually be transparent, but may be translucent or even opaque. The host material need only be pervious to that portion of the electromagnetic spectrum, which activates the photochromic substance, i.e., that wavelength of ultraviolet (UV) light that produces the open or colored form of the substance and that portion of the visible spectrum that includes the absorption maximum wavelength of the substance in its UV activated form, i.e., the open form. Preferably, the host color should not be such that it masks the color of the activated form of the photochromic compounds, i.e., so the change in color is readily apparent to the observer. Compatible tints may be applied to the host material as described in U.S. Pat. No. 5,645,767 in column 13, line 59 to column 14, line 3.
Most preferably, the polymeric organic host material is a solid transparent or optically clear material, e.g., materials suitable for optical applications, such as plano, ophthalmic and contact lenses, windows, automotive transparencies, e.g., windshields, aircraft transparencies, plastic sheeting, polymeric films, etc.
Examples of polymeric organic host materials which may be used with the photochromic compounds described herein include: polymers, i.e., homopolymers and copolymers, of the bis(allyl carbonate) monomers, diethylene glycol dimethacrylate monomers, diisopropenyl benzene monomers, ethoxylated bisphenol A dimethacrylate monomers, ethylene glycol bismethacrylate monomers, poly(ethylene glycol) bismethacrylate monomers, ethoxylated phenol bismethacrylate monomers, alkoxylated polyhydric alcohol acrylate monomers, such as ethoxylated trimethylol propane triacrylate monomers, urethane acrylate monomers, such as those described in U.S. Pat. No. 5,373,033, and vinylbenzene monomers, such as those described in U.S. Pat. No. 5,475,074 and styrene; polymers, i.e., homopolymers and copolymers, mono- or polyfunctional, e.g., di- or multi-functional, acrylate and/or methacrylate monomers, poly(C1C12 alkyl methacrylates), such as poly (methyl methacrylate), poly(oxyalkylene) dimethacrylate, poly(alkoxylated phenol methacrylates), cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polyurethanes, polythiourethanes, thermoplastic polycarbonates, polyesters, poly(ethylene terephthalate), polystyrene, poly(alpha methylstyrene), copoly(styrene-methyl methacrylate), copoly(styrene-acrylonitrile), polyvinylbutyral and polymers, i.e., homopolymers and copolymers, of diallylidene pentaerythritol, particularly copolymers with polyol (allyl carbonate) monomers, e.g., diethylene glycol bis(allyl carbonate), and acrylate monomers, e.g., ethyl acrylate, butyl acrylate. Further examples of polymeric organic host materials are disclosed in the U.S. Pat. No. 5,753,146, column 8, line 62 to column 10, line 34, which disclosure is incorporated herein by reference.
Transparent copolymers and blends of transparent polymers are also suitable as host materials. Preferably, the host material or substrate for the photochromic polymeric coating composition is an optically clear polymerized organic material prepared from a thermoplastic polycarbonate resin, such as the carbonate-linked resin derived from bisphenol A and phosgene, which is sold under the trademark, LEXAN; a polyester, such as the material sold under the trademark, MYLAR; a poly(methyl methacrylate), such as the material sold under the trademark, PLEXIGLAS; polymerizates of a polyol(allyl carbonate) monomer, especially diethylene glycol bis(allyl carbonate), which monomer is sold under the trademark CR-39, and polymerizates of copolymers of a polyol (allyl carbonate), e.g., diethylene glycol bis(allyl carbonate), with other copolymerizable monomeric materials, such as copolymers with vinyl acetate, e.g., copolymers of from 80-90 percent diethylene glycol bis(allyl carbonate) and 10-20 percent vinyl acetate, particularly 80-85 percent of the bis(allyl carbonate) and 15-20 percent vinyl acetate, and copolymers with a polyurethane having terminal diacrylate functionality, as described in U.S. Pat. Nos. 4,360,653 and 4,994,208; and copolymers with aliphatic urethanes, the terminal portion of which contain allyl or acrylyl functional groups, as described in U.S. Pat. No. 5,200,483; poly(vinyl acetate), polyvinylbutyral, polyurethane, polythiourethanes, polymers of members of the group consisting of diethylene glycol dimethacrylate monomers, diisopropenyl benzene monomers, ethoxylated bisphenol A dimethacrylate monomers, ethylene glycol bismethacrylate monomers, poly(ethylene glycol) bismethacrylate monomers, ethoxylated phenol bismethacrylate monomers and ethoxylated trimethylol propane triacrylate monomers; cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, polystyrene and copolymers of styrene with methyl methacrylate, vinyl acetate and acrylonitrile.
More particularly contemplated is use of the photochromic naphthopyrans of the present invention with optical organic resin monomers used to produce optically clear coatings and polymerizates, i.e., materials suitable for optical applications, such as lenses for use in a pair of spectacles, e.g., plano or ophthalmic spectacle lenses, or for use as contact lenses. Optically clear polymerizates may have a refractive index that may range from about 1.35 to about 1.75, e.g., from about 1.495 to about 1.66.
Specifically contemplated are polymerizates of optical resins sold by PPG Industries, Inc. under the CR-designation, e.g., CR-307 and CR-407, and polymerizates prepared for use as hard or soft contact lenses. Methods for producing both types of contact lenses are disclosed in U.S. Pat. No. 5,166,345, column 11, line 52, to column 12, line 52, which disclosure is incorporated herein by reference. Additional polymerizates contemplated for use with the photochromic hydroxylated/carboxylated naphthopyrans of the present invention are polymerizates used to form soft contact lenses with high moisture content described in U.S. Pat. No. 5,965,630 and extended wear contact lenses described in U.S. Pat. No. 5,965,631, both disclosures of which are incorporated herein by reference.
More particularly, contemplated is use of the photochromic naphthopyrans of the present invention with optical organic resin monomers used to produce optically clear coatings and polymerizates, i.e., materials suitable for optical applications, such as for example piano and ophthalmic lenses, windows, and automotive transparencies. Such optically clear polymerizates may have a refractive index that may range from about 1.48 to about 1.75, e.g., from about 1.495 to about 1.66. Specifically contemplated are optical resins sold by PPG Industries, Inc. under the designation CR-307 and CR-407.